chevychick76

Is there any way I can find out my gear ratio? My front differential is leaking and ism trying to see which one I need to buy to replace it so I can rebuild this one.

burnhedge

I don't see the year of the truck in your post or sig. I believe pre 96 all have codes in the glove box. Not sure about 96-98. If your not sure the truck is all original or you can't read the codes you'll have to pull the cover off the rear diff and check the ring gear.

chevychick76

It's a 98. It has the sticker on the box. I just don't know the codes.

chevychick76

Last time I took the diff cover off I wasn't sure of the numbers on the rings. I'm also not sure if it's stock but I think the only thing done was a 6 inch lift.

burnhedge

The ring gear will be stamped with two numbers. Say 37 and 9. These are the number of teeth on the ring and pinion gears. 37 divided by 9=4.11 gears.

Rpo codes are available many places online. West coast diffs has a good list just for what your looking for. These are the ones I know by heart for rear ends.
Gu4=3:08
Gu5=3:23
Gu6=3:42
Gt5=3:73
Gt6=4:10

chevychick76

I was hoping I had 3.73 but I'm thinking they are 3.42 which means I'll be wanting to upgrade them. What would be the best suggested ratio?

burnhedge

Most k1500's are 3:42.

It depends on a lot of factors,
What size tires you want to run is most important. That way you know what gears will bring you back to stock "power" . Then go from there depending on what you want to do with the truck.

I'm assuming you are running large tires since you mentioned a lift.

chevychick76

It's a 4x4 so yes I'm running 35/12.50/16's. I had 36's and down sized. But of couse I want the power to pull and play pretty much.

chevychick76

burnhedge

4:56 would probably be the best choice. May want to do 4:10 if it's a daily driver that you want to cruise down the highway with.

You may have limited choices in a 8.25 front diff, but I would think 4:56 would be available.